高温除尘脱硝一体化装置SCR催化剂选型设计分析

Selection and design of SCR catalyst for a high-temperature dedusting and denitration integrated device

以某350 MW燃煤发电机组的高温除尘脱硝一体化示范项目为研究对象,对比了采用常规高温高尘布置与高温低尘一体化布置的选择性催化还原(SCR)脱硝系统。通过分析2种布置方式对SCR催化剂选型设计的影响,论述了高温除尘一体化布置的技术经济优势。通过横向对比和相关数据分析得出,一体化布置方式有助于降低催化剂的物理磨损、堵灰风险和化学中毒风险。催化剂可采用35孔的小孔径蜂窝型,减小脱硝装置的体积。常规高温高尘布置下的SCR催化剂化学寿命约为3年(24000 h),而在清洁环境下工作的催化剂寿命可延长至5~6年。一体化布置方式还有助于降低SCR脱硝装置的投资、造价和运行成本。该研究对高温除尘脱硝一体化布置下的SCR脱硝装置的科学设计、技术发展与应用具有的重要意义。

A demonstration project of a high-temperature dedusting and denitration integrated device for a 350 MW coalfired power generation unit was taken as the research object,and the device′s high-temperature low-dust layout was compared with the regular high-temperature high-dust layout. The impact of the two layouts on the selection and design of SCR catalyst was analyzed from technical and economic aspects.Through the lateral comparison and analysis on related data,it is concluded that integrated arrangement can alleviate the risk of wear,ash blockage and chemical poisoning of the catalyst. Selecting small aperture honeycomb-shaped catalyst with 35 holes can reduce the total volume of the catalyst. The chemical life of SCR catalyst can be extended from 3 years(24 000 h)under conventional high-temperature high-dust arrangement to five to six years in a relatively clean environment. At the same time,this integrated arrangement contributes to reducing the investment and operation cost of the device. Studying the integrated arrangement is of great significance for the scientific design of SCR denitration device and its technology development.